CCL:G: ONIOM

 Sent to CCL by: "Marius Retegan" [marius.s.retegan]![gmail.com]
 Hi,
 First of all I would like to say that I don't see the sens on using a
 three layer ONIOM in which two of the layers are calculated with PM3
 and AM1. These to methods provide similar
 results and I think that it would be logical to use a 2 layer ONIOM
 (b3lyp/pm3 or b3lyp/am1).
 About the error, I can't give you an explanation since I don't know
 how you did make your input. I find that doing ONIOM inputs for
 Gaussian can be hard to very hard if you don't have GaussView, and
 even if you have can still be tricky the first time you try it.
 Another tool that  you can use to create inputs ( in the case that you
 don't have GV) is Gabedit.
 A new version of Gabedit (2.0.11) is available.
 Here is a list of the significant changes between 2.0.11 and 2.0.7:
 - Bugs were fixed.
 - PCGamess is now supported by Gabedit
 - Q-Chem is now supported by Gabedit
 - New windows for draw IR, Raman and UV/Visible spectrum.
 - The ONIOM method of Gaussian is now supported
 You can download this new version from :
 http://lasim.univ-lyon1.fr/allouche/gabedit/download.php
 Hope this helps
 Marius Retegan
 On 6/13/07, Pankaj R. Daga pdaga*_*olemiss.edu <owner-chemistry-,-ccl.net>
 wrote:
 
 Hi everybody,
 I am new learner of ONIOM. I am dealing with a system with more than 1000
 atoms in it. I have divided the whole system into 3 layers. When I am
 running the calculation with  B3LYP/6-31G*:PM3:AM1, the calculations run
 well. But when I use the same system with force field, amber or uff, then
 program ends abruptly saying
 "MM function not complete"
 I don't know if there is any need to add force-field parameters and if yes
 then how? I see, there are a lot of reports available in the literature
 using Amber force field in ONIOM method.
 I will be grateful to you if you could suggest me the way out.
 Thanx and Regards
 Pankaj
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 If your ship doesn't come in, swim out to it.......Jonathan Winters
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 Pankaj R. Daga                     |
 Department of Medicinal Chemistry  |  e-mail:  pdaga_at_olemiss.edu
 417 Faser Hall, School of Pharmacy |  fax:          +1-662-915-5638
 University of Mississippi          |  phone:        +1-662-915-1853
 University, MS, 38677-1848         |
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